Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROUND OF THE INVE~TION
Field of the Invention
This invention relates generally to record playing
apparatus and, more particularly, is directed to a releasable
cover locking device for a record playing apparatus.
Description of the Prior Art
Audio and video record pla~ers are well-known in
the art in which a record disk is rotated at a relatively
high speed while information is reprocluced therefrom. Because
of the high rotational speed used, it may be dangerous if the
u.ser inadvertently touches or contacts the disk during the
reproduction operation. Further, in t:he case of a video disk,
where a laser beam is used to reproduce signals recorded on the
disk, it may be dangerous iE the laser beam comes into contact
with the user. It has therefore been tlecessary, in many in-
stances, to provide a cover on the recorcl players so as to
avoid the above-described danger~s.
GeneralLy, such covers arc l~inp,edly ~securecl at the
rear edges thereof to the record plflyer l~odies and the front oE
each cover includes a lat:ch wllicll cooperate~s in a matinp, arrarlge-
ment with a locking mecllanism oE the al-p~r<ltu.s. ~ push-button
or the like is provided or releasirlg ~he la~.ch from the locking
me~l,$nism so tl~t the cover can be opened. Ilowever, ;.~ the loclcing
mecl~nism is opened or released while the record disk is still
rotating, the aforementioned dangers are still present.
_JECTS AND SUr.`~RY OF THE INVFNTION
Accordingly, it is a principal object of this inven-
tion to provide a releasable cover locking device that avoids
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the above-described difficulties etlcoulltered with the prior
art.
~ Iore particularly, it is an object of this invention
to provide a releasable cover locking device that ensures a
high degree of safety during operation of a record playing
apparatus with which it is used.
It is another object of this invention to provide a
releasable cover locking device having a locking mechanism
which is adapted to be released only after the rotational
speed of a record disk is less than a predetermined safe value.
It is still another object of this invention to pro-
vide a releasable cover locking device having a locking mecha-
nism which is adapted to be released in an electrically control-
lable operation when power is supplied to the record playing
apparatus and when the speed of rotation of the record disk
therein is less than a predetermined vaLue, and is adapted to
be released in a mechanically controllable operation when the
source of power to the apparatus is interrupted.
In accordance with an aspec~ o~ this invention, a
releasable cover locking device is provided for a r~cordi.ng
and/or reproducing apparatus o~ the ~ype in wllich a record
medium is adapted to be moved whetl power is supplied to the
apparatus, the releasable cover locking device including re-
leasable locking means; Eirst release means ~or releasing the
locking means when power is supplied to the apparatus and
when the speed of movement oE the record medium is less than
a predetermined value; and second release means for releasing
the locking means when t.lle p~wer supplied to the apparatus is in-
terrupted.
The above, and other, objects, features and advan-
tages of the present invention will become readily apparent
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from the ensuing detailed descrip~ion of an illustrative em-
bodiment of the invention which is to be read in connection
with the accompanying drawings.
BRIEF DESCRIPTION ()F THE DRAT.~IINGS
Fig. 1 is a perspective view of a record player
with which the present invention can be utilized;
Figs. 2(A) - (D) are side plan views of a locking
mechanism according to one embodiment of this invention in
various operative conditions;
Fig. 3 is a perspective view of a releasable cover
locking device according to one embodiment of this invention;
Fig. 4 is an enlarged persepctive view of an elec-
trical lock releasing mechanism that can be utilized in the
releasable cover locklng device of Fig. 3;
Fig. 5 is a side plan view of the electrical lock
releasing mechanism of Fig. 4;
Fig. 6 is a side plan view of a stop lever of a mecha-
nical lock releasing mechanism that can be utilized in the re-
leasable cover locking device of Fig. 3;
Fig. 7 is a side plan view oE an inclined arm of a
mechanical lock eleasing mechanism that can be used with the
releasable cover locking device o Fi~. 3; and
Figs. 8(A) and 8(B) are top plan views of a mechanica1
lock releasing mechanism that can be used with the releasable
cover locking device of Fig, 3.
DETAILED DESCRIPTION OF A P EFERRED EMBODIMENT
Referring to the drawings in detail, and initially
to Fig. l thereof, there is shown a record playing apparatus
1 of the 1sser disk type with which the present invention ls
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adapted to be used. As shown t~r~in, ~ecord playing apparatus
1 includes a rotatable drive sha~t 2 for rotating a video disk
3 at a high speed. A laser beam 5, ShOWII by the dashed line
in the figure is generated by a laser tube 4 and is directed
to the underside or lower surface of video disk 3 by an opti-
cal system (not shown) and the beam,when reflected therefrom,
is used to reproduce video signals recorded on the disk.
As previously discussed, however, a dangerous situa-
tion may result if the user touches or contacts video disk 3
while the latter is rotated at such high speed. This danger
is increased if the user inadvertently comes into contact with
laser beam 5. Accordingly, record playing apparatus 1 includes
a cover or lid 6 which is hingedly attached ~t its rear ed~e
6A to the apparatus by means of hinges 7. The cover 6 is adap-
ted to be lockingly engaged to the apparatus by means of a lock
bar or latch 8 provided on the front edge 6B of cover 6 and
a locking mechanism 9 is provided at the front end of the appa-
ratus. In particular, locking mechanism 9 cooperatively enga-
ges with lock bar 8 when cover 6 is closed to prevent the cover
from being inadvertently opened. A cover opening push-button
10 is provided on the front panel oE the apparatus for releas-
ing, that is, unlocking, locking mechanism 9 so that cover 6
can be opened, for example, to remove or change the video disk.
As previously discussed, however, if cover 6 is permitted to
be opened while video disk 3 is rotating at a high speed, a
dangerous situation may result.
Accordingly, the present invention provides a releas-
able locking mechanism which is only released when the rota-
tional speed of video disk 3 is less than a predetermined value
(includine the stopped condition~. In particular, a lockin~
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mechanism 11 is provided in pla(~e of lockin~J nlechanisln 9 and
is shown in F'ig. 2(A) in the conditioTI where cover 6 is open.
Locking mechanis~ 11 includes a locking lever 12 and a de-
tecting lever 13, both pivotall~ supported at their lower
ends by a rotatable support shaft 14. Locking lever 12 is
adapted to engage and retain lock bar 8 and is formed at its
upper end with a bar engaging portion 12A which is bent so
as to have an arcuate shape centered about support shaft 14,
whereby lock bar 8, and consequently, cover 6, can be locked
in a closed position. Locking lever 12 is also provided at
its lower end with a pin 12B which pr~jects horizontally
~rom one side thereof and also includes a pivot rod 12C which
projects horizontally from the opposite side thereof.
Detecting lever 13 is formed at its upper end with
a detecting surface 13A having a gentle arcuate confi~uration
in opposing relation to engaging portion 12A of locking lever
12. Detecting lever 13 also includes a shoulder 13B at the
lower end thereof. A tension spring 15 is connectecl between
a pin 12D at the lower end of locking lever 12 ancl an arm 13C
of detecting lever 13 so as to bias b~lr engaging portion 12A
and detecting surEace 13A toward each otller about sul-port sh~ft
14. The extent that bar engagillg por~:ion 12A and detecting
surace 13A are biased toward eaeh otller is limitecl by the
abutting engagement of shoulder 13B on pin 12B, as shown in
Fig. 2(A). Further, the angular relation of locking lever 12
and detecting lever 13 about support shaft 14 is determined by
a spring 16 which is connected at one end to the apparatus and
at its other end to detecting lever 13 so as to bias locking
lever 12 and detecting lever 13 together in a clockwise direc-
tion, as viewed in Fig. 2(A), about support shaft 14.
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In operation, as cover 6 is closed, lock bar 8 is
guided by a lock guide 8A as it descends and approaches lock-
ing mechanism 11 of the apparatus. As it descends, lock bar
8 abuts agains~ detecting surface 13A and the upper arm o~
locking lever 12 ~o pivotally separate locking lever 12 and
detecting lever 13 about support shaft 14 and against the
action of tension spring 15. In particular, locking lever 12
is displaced in a clockwise direction about support shaft 14
and detecting lever 13 is displaced in a counter-clockwise
direction about support shaft 14, as shown in Fig. 2(B). As
lock bar 8 continues its descent past detecting surface 13A
of detecting lever 13, springs 15 and 16 operate to rotate
locking lever 12 and detecting lever 13 about support shaEt
14 to their original positions so as to lockingly enga~,e lock
bar 8 therebetween, and thereby lock cover 6 in its closed
position, as shown in Fig. 2(C). To open cover 6, locking
lever 12 is pivoted clockwise, as viewed in Fig. 2(D), against
the tension of spring 15,to allow lock ~ar 8 to be removed
from locking mechanisTn 11, ancl ~hereby perm:Lt cover 6 to be
opened.
Referring now to Fig. 3, thcre is shown a release
mechanism according to one embodimerlt oE ~his i.nvention for
releasing or unl.ocking locking mechani.sm 11. ~.s shown there-
in, an electrically controlled portion oE the release inechanism
includes an electromagnetic plunger 20 having a reciprocable
rod 21 with its free end engaging a release link 23. In par-
ticular, as shown more clearly in Figs. 4 and 5, release link
23 includes an upstanding driven arm 24 and an inclined, up-
standing transmitting arm 26 connected together by a connecting
member 23A. Arms 24 and 25 having coaxial apertures 2~ and 29
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at their lower ends through which support shaft 14 is inserted
to rotatably journal release link 23 thereabout. Further, an
engaging recess 25 of a U-shaped configuration is provided at
the upper end 24A of driven arm 24 for en~aging a drive pin 22
extending horizontally from reciprocable rod 21. In like man-
ner, an actuating surface 27 is provided at the upper end 26A of
transmitting arm 26 for engaging pivot rod 12C extending hori-
zontally from one side of locking lever 12.
When power is supplied to record playing apparatus 1,
a motor 31 rotates video disk 3 at a desired rotational speed
during the reproducing operation. A detecting device 30 de-
tects the rotational frequency, that is, the speed, of video
disk 3 and supplies a corresponding output to electromagnetic
plunger 20. Normally, when video disk 3 is rotated at a high
speed, detecting device 30 supplies an appropriate signal to
electromagnetic plunger 20 to maintain rod 21 in an extended
position. This results in locking mecllanism 11 mai.ntaining
lock bar 8 and cover 6 in their respec~ive locked conditions.
The apparatus further inclu(les a cover opening but-
ton 33 which, when depressed, a~ sllown more particularly in
Fig. 6 by the dot-dash lines, causes n pressure surEace 33A
thereof to abut against a driven arm ~39~ oE a stop lever 39 to
bias the latter about support shaft 14 and a~,ainst a return
spring 42. As a esult, an actuating arm 39~ of stop lever
39 engages a corresponding operating portion 32A of a micro~
switch 32 which controls motor 31 to stop the rotation of vi-
deo disk 3. When the speed or frequency of rotation of video
disk 3 falls below a predetermined value (which includes the
stopped condition~, plunger 20, in response to the output from
detecting device 30 retracts reciprocable rod 21. This, in
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turn, causes release link 23 and accordingly, transmitting
arm ~6 thereof, to be rotated in the clockwise direction, as
viewed in Fig. 5. As a result, locking lever 12 is rotated
clockwise, as viewed in Fig. 2(D), against the tension of
spring 15 so as to release lock bar 8, whereby cover 6 can
be opened. It should be appreciated that, with this arrange-
ment, cover 6 can only be opened when the rotational speed
of video disk 3 is low and, in fact, when it it less than a
predetermined safe speed.
If, however, the power supplied to record playing appa-
ratus 1 is turned OFF or interrupted while cover 6 is in its
locked condition, electromagnetic plunger 20 is not actuated
to release locking mechanism 11. In such case, a mechanically
controlled portion of the release mechanism of Fig. 3 is pro-
vided. In particular, and referring to Figs. 3, 7, 8(A) and
8(B), an electromagnetic plunger 34 having a reciprocable rod
35 with an upstanding pin 36 at the free end thereoE is pro-
vided. A swing or positioninp, link 38 i9 pivotally supported at one end
thereof about a pivot pin 37 and is adapted ~or mov~ment ln
the horizontal. and vertical dir~ctions. Swing linlc 38 is nor-
mally biased about pivot pin 37 in a counter-clockwise dircc-
tion, as vie~ed in Fig. 8(A), by means o~ a tension sl)ring
38C (Fig. 3). A recess 38B is provlded approximate].y midway
along one edge of swing link 38 within whicll uDstanding pin
36 is located for engagement therewith during all vertical
and horizontal movements of swing link 38.
An operating link 41 is integrally attached at one
end thereof to the lower end of stop lever 39 and is arranged
i in parallel relation to support shaft 14. Operating link 41 also
includes a slot 41A through which the free end 33A of swing
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link 38 is disposed for lateral movement therein. The other
end of operating link 41 is integrally attached to an upstand-
ing, inclined arm 40 which is adapted to pivot locking lever
12 in the release direction thereof, that is, clockwise as
viewed in Fig. 2(D).
When power is supplied to record playing apparatus
l, electromagnetic plunger 34 is actuated to its inGperative
position. In particular, during such condition, electromag-
netic plunger 34 retracts rod 35 to the left, as shown in Fig.
8(A), whereby to move operating link 41 in the same direction
by means of swing link 38. As a result, stop lever 39 is po-
sitioned in opposing relation to microswitch 32 and arm 40 is
posltioned out of engagement with pivot rod 12C of locking
lever 12. In such case, when power is suppliecl to record
playing apparatus 1, video disk 3 is rotatated at a high speed
during the reproducing operation. To open cover 6, cover
opening button 33 is pressed so as to actuate microswitch 32
through stop lever 39. This, in turn, controls motor 31 for
stopping the rot~tion of disk 3. At ~hls time, detecting
device 30 detect~ the reduction in s,t)eed of video dlslc 3 below
a predetermined value, and actuates eLectroma~,netic plunger
20 to pull rod 21 inwarclly which, ln t~lrn, actuates release link
23 to release locking lever 12. 'rhus, when cover 6 i9 opened,
the rotational speed of video disk 3 has been reduced to a
safe speed to prevent any possible danger to the user.
If power to record: playing apparatus 1 is
interrupted or turned OFF so that electromagnetic plunger 20
does not retract rod 21, rod 21 is maintained in its extended
position and locking mechanism 11 is retained in its locked
configuration. However, at such time, the power to electro-
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magnetic plunger 34 is also interrupted whereby sprin~ 38Cfunc~ions to return swing link 38 to the position shown in
Fig. 8(B). As a result, the free end 3~A of swing link 38
biases operating link 41 to the right, as viewed in Fig. 8(B).
This is also accomplished by means of return spring 42 which
also functions to bias stop lever 39, and therefore operat-
ing link 41, in ~Ire same direction. It should be appreciated
that regardless of the position of stop lever 39 along support
shaft 14, driven arm 39A of stop lever 39 is always in opposing
relation to cover opening button 33. However, as shown in Fig.
8(B), at such time, actuating arm 39B of stop lever 39 is re-
moved from its opposing relation to microswitch 32, and an ac-
tuating surface 40A of arm 40 is in an engaging relation with
pivot rod 12C oi locking lever 12. To open cover 6 at such
time, cover opening button 33 is pressed so that pressure sur-
face 33A thereof actuates drivem arm 39A of stop lever 39 and
thereby rotates the latter about support shaft 14 in the coun-
ter-clockwise direction, as viewed in Fi~. 3. This, in turn,
causes arm 40 to also rotate in the ~samc clirection through
operating link ~1, as indicated by arrow C in li.g. 3. As A
result, lockin~ lever 12 is rotated in the clockwl~se directi.on,
as viewed in Fig. 2(D), to release lock bar 8, and thereEore,
cover 6.
~ aving described a specific preferred embodiment of
the invention with reference to the accompanying drawings, it
is to be understood that the invention is not limited to that
precise embodiment, and that various changes and modifications
may be effected therein by one skilled in the art without de-
parting from the scope or spirit of the invention as defined
in the appended claims.
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